Patient hoist and scale

ABSTRACT

A patient hoist having a base, a load sensor mounted to the base and a mast assembly including an elevation arm and a body support member extending from the load sensor. The patient hoist is used to determine a patient&#39;s weight while the patient is assisted to a standing position or suspended.

This application is a continuation application of application Ser. No.08/794,680 filed Feb. 3, 1997, now issued as U.S. Pat. No. 5,892,180.

BACKGROUND OF THE INVENTION

The present invention relates to a patient hoist, and more particularly,relates to a way to determine the weight of a patient supported by apatient hoist.

FIELD OF THE INVENTION

In the healthcare field, it is often desirable to assist a patient to astanding or suspended position. This is particularly needed to helpsupport the infirm or disabled who may lack the strength or coordinationto raise themselves. To assist in supporting these patients, it iscommon to have a patient hoist which is a lift or a stand. A caregiveris normally required to assist a patient in using a lift or stand.

A lift is a patient hoist, where a patient is placed in a sling orstretcher on a bed or chair, and is then lifted by a mobile arm-type ofdevice. In a lift, the patient is completely supported from an overheadposition, and has no active role in supporting themselves or assistingin being raised. A lift is used to temporarily raise a patient ortransport them without discomfort. Such a lift is illustrated in U.S.Pat. No. 4,482,783.

A stand is a different type of patient hoist which is used to raise apatient from a sitting position to a generally standing position. Astand is normally smaller than a lift, with an upright member and apivotably mounted arm or support member moved by an elevation arm oractuator. When supported by a stand, the patient stands at an angle, andholds support bars.

A strap-type sling is normally used with a stand to assist in supportinga patient. The sling goes behind the patient's back and under thepatient's arms and is then suspended from the stand. The patient is thenlifted to a generally erect position. Once the patient is lifted, thestand may be moved to reposition the patient to a new desired locationor other patient care procedures such as changing clothes or toiletingmay be done. Alternatively, the patient may step off of the stand andwalk away. Such a stand is illustrated in U.S. Pat. No. 5,022,106.

A stand may also be used with a larger sling to raise and suspend thepatient; however, a lift is normally more efficient for this operation.Another alternative is to lower a stand's support bars to a comfortablehand level and remove the foot plate, the stand may be used to assistthe patient in walking.

In addition to helping support and transport patients, nursingfacilities also have a need to weigh patients on a regular and frequentbasis. If the weighing activity can be combined with a patient transfer,a weighing step is eliminated which reduces the discomfort of thepatient and saves the caregiver time and labor.

It has been known to incorporate a weighing system or scales into apatient lift where the patient is completely suspended from a mobilearm. These lifts generally show scales mounted at the end of the mobilearm directly over the patient or directly supporting the mobile arm.

However, there have been a number of drawbacks in attempts toincorporate a weighing system with a patient stand. Thus, a separateweighing step has been required. This requires additional time andeffort for the caregiver and can cause additional discomfort to thepatient. There is a need for a manner to accurately measure a patient'sweight on a patient stand since the patient is generally standing at anangle, and is holding hand-holds, thus dissipating the patient's weight.

SUMMARY OF THE INVENTION

The present invention is a patient hoist configured to measure apatient's weight. The patient hoist is used to assist the patient from agenerally sitting to a generally standing position or alternately tosuspend the patient. The patient hoist has a base, a load sensor mountedto the base, and a mast assembly bearing on the load sensor. Once thehoist is adjacent to the patient, the patient is placed in a sling, andassisted to a standing position or suspended. The hoist may then bemoved to reposition the patient, and the weight of the patient can bedetermined from the load sensor and an attached display. Once relocatedor weighed, the patient can be lowered and assisted to a new position.

Accordingly, it is an object of the present invention to provide apatient hoist to assist in supporting infirm or disabled patients.

A further object of the invention is to provide a scale wherein thepatient's weight may be measured while the patient is being supported bythe hoist.

It is a further object of certain embodiments of this invention toaccurately measure the patient's weight while the patient is standinggenerally at an angle, and holding hand-holds.

Another object of the present invention is to provide a patient weighingdevice wherein the patient is not discomforted, and the weighinginvolves a minimal amount of time and effort for the caregiver.

Further objects, features, and advantages of the present invention shallbecome apparent from the detailed drawings and descriptions providedherein.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a preferred embodiment of the invention.

FIG. 2 is a perspective view of an alternate preferred embodiment of theinvention.

FIG. 3 is a perspective enlarged view of the base portion of a preferredembodiment as shown in FIG. 2.

FIG. 4 is a partial, enlarged view of the base portion of a preferredembodiment of the invention as shown in FIG. 2.

FIG. 5 is a perspective view of an alternate preferred embodiment of theinvention.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiments illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended. Any alterations and further modificationsin the described device, and any further applications of the principlesof the invention as described herein are contemplated as would normallyoccur to one skilled in the art to which the invention relates.

The patient hoist of the present invention allows a caregiver to assista patient from a generally sitting position to a generally standingposition or to completely suspend the patient. The present inventionincorporates a scale or load sensor to accurately measure the patient'sweight while the patient is supported by the patient hoist.

Referring now to FIGS. 1 and 2, patient stand 10 includes base 15, andmast assembly 25. Base 15 has base tube 16, first leg 17 and second leg18. Legs 17 and 18 are mounted to controllably pivot about pins 17 a and18 a, respectively. Wheels 13 are normally attached to first leg 17 andsecond leg 18. As is best shown in FIG. 2, leg spreader handle 20 ispivotably mounted around axis P1 and extends from base tube 16. Spreaderhandle 20 is engaged to spreader bars 21 which are further engaged tofirst leg 17 and second leg 18. Spreader handle 20 may be pivoted aboutaxis P1 to move first leg 17 and second leg 18 into a spread position,or reversed to narrow their spread. Handle 20 engages cross brace 23which is connected to base 15 by support rods 24 a and 24 b. Cross brace23 includes detents 23 a, 23 b, 23 c corresponding to different spreadpositions of handle 20.

Mast assembly 25 extends from base tube 16. Near the base of mastassembly 25 foot pad 40 is attached and included. Foot pad 40 has a steparea 44, an alignment bracket 43 and mounting hooks 41. Mounting hooks41 are engaged to hinge pins 42 extending from mast assembly 25.

Mast assembly 25 has a mast 26 extending in a generally verticaldirection. Mast 26 is connected to body support member 28 through pivot31. Body support member 28 has sling hooks 30, and hand-holds 36.Elevation arm or actuator 32 extends from the base of mast assembly 25to body support member 28. Electric motor 56 engages elevation arm 32,and can be used to extend or retract elevation arm 32 thereby raising orlowering body support member 28. Motor 56 is powered from power supplyhousing 55 mounted on mast 26. In one preferred embodiment, actuator 32is an electronic ball screw actuator.

Steering handle 53 is attached to mast 26. Mast 26 further has at leasttwo wiring holes 60 and 61 through which wires may be threaded to loadsensor 45 (see FIG. 4), power supply housing 55, motor 56 or display 50.Load display 50 is mounted on mast assembly 25 and is operativelycoupled by wiring to load sensor 45. Preferably, load display 50 has adigital readout. Shin pad 38 is mounted on mast assembly 25 facing thepatient. A sling 34 may be suspended from sling hooks 30 (see FIG. 2).

Referring now to FIG. 3, an enlarged section of base 15 of stand 10 isshown. Leg spreader handle 20 is mounted via a pivot point to base tube16 of base 15. Spreader bars 21 extend from spreader handle 20 to firstleg 17 and second leg 18 as shown in FIG. 2. Spreader handle 20 may berotated to adjust the stand's stability via the spread of first leg 17and second leg 18. Base tube 16 has opening 62 adjacent to mast assembly25 to allow the placement of wires.

Referring to FIG. 4, an enlarged, partial section of base 15 of stand 10is shown. Mast assembly 25 is mounted to base 15 via mating plate 46 andload sensor 45, preferably a load cell. Mast assembly 25 is secured tomating plate 46 via three bolts 47. Mating plate 46 is secured to loadsensor 45 via four socket cap screws 48. Load sensor 45 is situatedwithin base tube 16 and is secured to base tube 16 by four bolts 49.Opening 62 adjacent to mast assembly 25 allows the placement of wires tooperatively connect load sensor 45 with load display 50 (see FIG. 2) andpower supply housing 55.

As illustrated in FIG. 5, an alternate preferred embodiment of theinvention is shown. FIG. 5 shows a lift 100 having a base 115 and a mastassembly 125. Base 115 is essentially similar to base 15. Base 115 hasfirst leg 117, second leg 118 and base tube 116. First leg 117 andsecond leg 118 pivot around pivot points 117 a and 118 a, respectively.The spread of these legs is controlled by spreader handle 120 pivotablymounted to base tube 116 along axis P1. Spreader bars 121 extend fromspreader handle 120 to first leg 117 and second leg 118 as shown.Spreader handle 120 is guided by a cross brace as previously illustratedin FIG. 2.

Mast assembly 125 is similar to mast assembly 25 and extends from base115 by being mounted to a load sensor (not visible) mounted in base tube116. Mast assembly 125 has a mast 126 and a mobile arm 128 pivotablymounted via pivot point 131 to mast 126. Sling hooks 130 are suspendedfrom mobile arm 128. Elevation arm 132 is mounted from mast 126 tomobile arm 128 and is used to control the height of mobile arm 128.Additionally, handle 153 and load display 150 are mounted on mastassembly 125.

For all of the illustrated preferred embodiments, to ensure accuratereadings, it is important that mast assembly 25 or 125 engage loadsensor 45 in a manner such that the full weight of mast assembly 25 or125 bears on load sensor 45. For this purpose, spacer plate 65 may beinserted between load sensor 45 and base tube 16 to raise load sensor45. Alternately, the height of mating plate 46 may be varied. Forpurposes of illustration, a spacer plate of ⅝″ is used and a matingplate with a height of ¼″ is used.

The use of various load sensors are envisioned for use with stand 10 orlift 100. These could be mechanical or electrical scales such as straingauges, transducers, springs or otherwise, with the preferred sensorbeing a load cell. For purposes of illustration, a Sensortronics Model60060 load cell with a rated capacity of 1,000 pounds is used. It willalso be understood that the use of more than one load sensor where theweight is accumulated and totaled is envisioned. For instance,individual load cells could be mounted to each wheel of the hoist, orparallel load cells could be mounted within the legs of the base.

When the patient stand is used, stand 10 is positioned in front of thepatient. Spreader handle 20 is then rotated to spread first leg 17 andsecond leg 18 and make a more stable base arrangement. The patient'sfeet are then situated on step 44 of foot pad 40. A preferred belt typesling 34 is arranged around the back of the patient, under the patient'sarms and suspended from sling hooks 30. Motor 56 is then engaged toextend elevation arm 32. As elevation arm 32 is extended, it raisessupport member 28 around pivot 31. This is continued until the patientis completely supported by foot pad 40 or body support member 28 and thedesired height is reached.

When the patient lift is used, lift 100 is placed adjacent the patientand stabilized similarly to stand 10. A sling is placed under thepatient and suspended from hooks 130. Mobile arm 128 is then raised byelevation arm 132 to raise the patient.

At this point, the patient's weight is completely supported by mastassembly 25 or 125. Mast assembly 25 or 125 engages and is completelysupported by load sensor 45. Display 50 or 150 is operatively coupled toload sensor 45 and displays the patient's weight.

It will be appreciated, that display 50 or 150 will need to becalibrated in the stand's unloaded state to compensate for the weight ofmast assembly 25 or 125. It will be further understood that mastassembly 25 or 125 may include additional pieces, or certain enumeratedpieces may be integrated. For instance, foot pad 40 could be connectedin a fixed manner to mast 26.

Alternatively, display 50 or 150 could be relocated on stand 10 or lift100, or could be remotely hand held and connected to stand 10 or lift100 via a cord or a transmitter and receiver. It will of course beunderstood that various alterations such as in wheels, hand-holds,elevation arms or motors may be used as would occur to one skilled inthe art.

A specific variation included within this invention includes the use ofa support sling with stand 10 which completely supports the weight ofthe patient. In this embodiment, the patient's feet would not besituated upon foot pad 40. Foot pad 40 could be removed or ignored inthis situation. The sling for this embodiment, (not pictured) could havea number of suspension points 30 on body support member 28, and couldsurround the patient to provide complete support.

A further embodiment of the invention envisions the use of the stand asan assisted walking device for the patient. Support member 28 may belowered to a comfortable hand level, and foot pad 40 removed so that thepatient may comfortably hold hand-holds 36 or support member 28 whilewalking.

All publications, patents, and patent applications cited in thisspecification are herein incorporated by reference as if each individualpublication, patent, or patent application were specifically andindividually indicated to be incorporated by reference and set forth inits entirety herein.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiment has been shown and described and that allchanges and modifications that come within the spirit of the inventionare desired to be protected.

What is claimed is:
 1. A patient hoist, comprising: a base; a spacermounted to said base; a load sensor mounted to said spacer; a mastassembly extending from said load sensor wherein said mast assemblyincludes an elevation arm and a body support member.
 2. The hoist ofclaim 1 where said load sensor is a load cell.
 3. The hoist of claim 2wherein said spacer is mounted on said base.
 4. The hoist of claim 2further comprising a footpad attached to said mast assembly.
 5. Apatient hoist, comprising: a base; a mast assembly extending from saidbase wherein said mast assembly includes a mast, a body support memberand an elevation arm connected between said mast and said body supportmember; and, a load sensor associated with said mast assembly; whereinsaid load sensor is associated with said mast assembly below theconnection of said elevation arm to said mast.
 6. The hoist of claim 5wherein said load sensor is a load cell.
 7. The hoist of claim 6 furthercomprising a display operatively coupled to said load cell andattachable to said mast assembly above said load sensor.
 8. The hoist ofclaim 6 further comprising a footpad attached to said mast assembly toapply loads from said foot pad to said mast assembly above said loadsensor.